The Internet is evolving from a human-oriented connection network in which humans generate and consume information, to the internet of things (IoT) network in which distributed elements, such as things and the like, exchange and process information. Internet of everything (IoE) technology may be an example of a combination of the IoT technology and big data processing technology through a connection with a cloud server.
In order to implement the IoT, technical factors such as a sensing technique, a wired/wireless communication and network infrastructure, a service interface technology, and a security technology are required, and thus, recently, technologies such as a sensor network, machine to machine (M2M), machine type communication (MTC), and the like for a connection between objects are being researched.
In an IoT environment, through collection and analysis of data generated in connected objects, an intelligent internet technology (IT) service to create a new value for people's life may be provided. The IoT may be applied to fields, such as a smart home, smart building, smart city, smart car, connected car, smart grid, health care, smart home appliance, or high-tech medical service, through the convergence and combination of the conventional information technology (IT) and various industries.
In general, in a home network system, an interphone is a device for confirming an identity of a visitor. When the interphone is installed inside a home and the doorphone is installed outside the home in the home network system, if a visitor presses the doorphone, a camera of the doorphone photographs a visitor's image and outputs the image to the interphone inside the home. Accordingly, a resident within the home may confirm a visitor's identity through the image output to the interphone.
However, when the interphone is used in the home network, if there is no resident within the home, it is not possible to confirm the visitor's identity and the visitor cannot enter the home. Accordingly, in the home network system, a method by which the resident can confirm the visitor's identity regardless of whether the resident is located within the home is needed.
Further, constructing a communication system between the doorphone outside the home and the interphone inside the home additionally costs much. In order to solve the problem, a method of confirming the visitor's identity without the installation of the doorphone outside the home and the interphone inside the home in the home network system is required.